Process of making aluminum sulfate.



I UNITED wea PATENT OFFICE.

ram: screams CARTER, "HA-rim neaxcn'snacxamon, AND 'rH'oMAs'nDwAnn GRAFTON, on north, GEURGTA.

rnoenss OF MAKING aneaznnmr 5mm.

1,037,591. Specification of Rome,in the -county of Floyd and State of Georgia, have invented certain new and useful Improvements in Processes of lvlaking Aluminum-Sulfate, cr wman the following is a full, clear, and exacuspecificationrr Our invention relates to the treatment of hydrated silicate ores of alumina, and particularly to the treatment of halloysite, a

hydrated silicate ore'of aluminum of conchoidal fracture, of pearly or waxy, to dull luster, of the general formula H Al,.Si,()., and'combined water; is

As an example of our method, we give the following procedure: After halloysite ore has been ground to the desired fineness, 'sulfuric acid of 30 degrees strength is added, the amount of hygroscopic'water ofabout 6 3 per. cent. being desirable. ,The' mix is then raised to! the tem'peratur'e'of one hundred degrees centigrade," and ke'p,t" at this temperature until substantially all the aluminum. content is dissolved, and the nonaluminum ingredients of the ore precipi; tated as'residue, the separation being effected as stated. 3

Heretofore halloysitey has never 1 been treated on a commercial scale with an acid solvent and the alumina put into solution.

Our process 'as set forth herein is a new process involving novel principles of treating aluminum ores, and further as applied to anore heretofore not used as a raw material for themmanufacture of aluminum sulfate. Our method-puts halloysite into solution to the extent of extracting aluminum compounds, and leaving the silica and other ingredients (cobalt, manganese nickel, etc)" in an insoluble form, which ingredients can be afterward extracted from this insoluble residue. Our method produces sulfate of aluminum free of such other in gredients as halloysite may contain.

We have discovered that the ore should be handled observing, certain conditions as set forth herein, and that the acid solvent should be added within certain limits and under conditions set forth herein in order to fully realize all the advantages of our invention. The ore is firstprepared by grind-- ing, crushing or rolling either in its natural Letters Patent. Patented Sept. 3, 1912.

Application filed september 'l, 1911. Serial No. 648,219.

- net of uniformfineness. An excess of riioistime is not objectionable. Preferably, a portlon of the original moisture of the ore should be retained in the ore, but such-portion of the original moisture/lost inprelum nary treatment, may be replaced subseq l 1 e I1 tl l. .ll l1e$OlVnt, preferably sulfuric acid, is ofsuch strength, added under such condition and'maintained at such temperatureias to chemicallyafi ect the ingredients, and cause separation and solution, as desired. l fl y We instance the following as one example of our process: The ore is converted in either-its natural or'moistened state to a powder-{preferably to a uniform'fineness.

Water is now added to bring'the mix to the desired consistency. The solvent, prefer-- ably" sulfuricaeid, is now added to the mix of desired consistency, and the resulting mixture brought to the desired temperature,

the amount of acid of known strength thus added beingsuflicient to:only dissolve the known per-cents of alumina at the desired temperature. The mix is preferably gradually heated and maintained atthe desired temperature until the aluminum compounds are dissolved'to the sulfate form and the other ingredients reniain/ undissolved. By observing the conditionsabove set forth the solution may be boiled after the reaction has set in'without throwing into solution the silica, cobalt, manganese, nicl l ingredients of the: .u e, ThQ-SBPS [ation is now made of the liquid from the insoluble residue, the liquid containing the sulfate of alumina. water of ab'sorption which" may be considcred1 in le terminingthe quantity of acid use other 7 Halloysite contai nsf fmoisture on The temperature of the mixture under treatment and the stren th of the solvent have a direct relationshlp, the higher the temperature the less the required strength of the'solvent, and vice versa, in all cases the temperature and solvent strengthmust be sotregulatedwith regard to each other as to produce the desired results to dissolvesubstantially all the aluminum content of the ore and leave behindsubstantijally all the non-aluminum ingredients of the ore.

It will be seen thatour discovery has opened the way for the first time to the successful recovery on a commercial scale of 01' in moistened state, preferably to a prodaluminum sulfate from halloysite, or like aluminum from pulverized hydrated silicate ores in a very short time thereby avoiding the necessity of first calcining aluminum ore as has heretofore been done with'certain aluminum ores other than silicates. Prior to our invention, silicated aluminum ores hai e been considered worthless, because after being calcined they would not yield to chemical treatment. Our process can, under favorableconditions, be carried out Within an hour, and requires but a small proportion of sulfuric acid, suflicient to hold the aluminum content in solution at the desired working temperature.

It will be understood that the above example is but one specific way of carrying out our invention, and that our method is not limited to the details given above, as so far as we are aware, we are the first to commercially recover aluminum from the natural silicated ores by chemical treatment.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. The herein described method of treating halloysite which consists in treating the raw ore with dilute sulfuric acid to dissolve the aluminum content.

The herein described method which consists in treating raw halloysite in the presence of moisture, with sulfuric acid to dissolve the aluminum content.

3. The method which consists in treating" raw halloysite in the presence of Water with dilute sulfuric acid of sufficierit strength to render the alumina soluble in the form of .sulfate and leaving behind the manganese, cobalt and nickel and other non-aluminum ingredients of the ore as a residue, and separating the dissolved aluminum content from the residue.

4. The method which consists in treating pulverized uncalcined halloysito in the presence of water with sulfuric acid of sufficient strength with relation to the temperature to render only the aluminum soluble and retain the same in solution, and leaving the nonaluminum constituents undissolved.

5. The method of producing aluminum sulfate which consists in pulverizing raw halloysite, then treating the same 1n the presence of water with sulfuric acid of sufficient strength with relation to temperature to dissolve substantially all the aluminum content'without affecting the other ingredicuts.

6. The method which consists intreating a pulverized natural silicated ore of aluminum with dilute sulfuric acid to dissolve the aluminum content, and separating the dissolved aluminum content from the residue.

In testimony whereof we affix our signatures in presence of two witnesses.

PERCY HUTCHINS CARTER. HARRY HORACE 'SIIACKTHITO'N.

THOMAS ElJWA'ltl) GRAFTON Witnesses W. 0. Parsons, P. I. MORRIS. 

